----- Original Message Follows -----
Thus spake "Scott Weeks" <surfer@mauigateway.com>
> From: "Stephen Sprunk" <stephen@sprunk.org>
>> ITYM two big transit LANs -- one must be prepared for a
>> switch to fail.
>
> These're going to be router-to-router connections (each
> AR is connected to both CRs) and I had thought about
> tying them all into one VLAN vs. PTP Gig-E. I was just
> trying to find out the operational benefits of either
design.If your physical topology is going to be PTP links, then
you should go with PTP at the logical level as well.
Making one topology look like another is generally a bad
idea.
This is what I decided to do.
Thanks everyone, your ideas (and those of a good friend)
helped me to find the KISS solution. 
scott